Overrunning clutches are commonly used to allow one way relative rotation between a pair of coaxial races. The mechanism that provides such selective rotation is the alternate engagement and disengagement of a plurality of spring energized metal wedging elements, typically rollers, between annularly spaced inner surfaces of the clutch A roller clutch will generally have some type of cage that provides a basic structure frame work to return the rollers and their energizing springs. A typical cage structure includes a pair of axially spaced side rails and a plurality of circumferentially spaced cross bars that join the two side rails together, thereby providing a plurality of roller retention pockets. Such a cage may be molded integrally of plastic in one piece, which is economical, and which allows complex shapes to be easily formed. However, in an environment such as the automatic transmission of a motor vehicle, the rollers are subjected to high speeds and heavy skewing forces that can push the roller ends very strongly into the cage side rails. Consequently, at least the side rails must be made of metal, generally stamped steel, in order to withstand the skewing forces.
Unlike integrally molded one piece cages, steel side rails must be separately structurally joined to the cross bars. The most common approach is to simply rivet the cross bars to the side rails. The strength of a rivet joint between cross bar and side rail is inevitably limited to the size of the rivet head, which may, in some cases, necessitate the use of many rivets, increasing the cost of manufacture. Another approach is to provide interfitting tabs and slots on the ends of the cross bars and the side rails, and to then locally deform or bend the tab or slot, or both, to provide a joint. In some cages, the cross bars are integrally stamped with one of the side rails, which makes for a complex and expensive shape. And any manufacturing operation involving metal deformation is difficult and expensive to carry out repetitively and accurately. This is especially true if the tab is an integral part of the side rail, because it is difficult to heat treat the main part of the side rail while leaving the deformable tab soft. Yet another approach is the use of resilient metal clips that are pressed over the cross bars and side rails to retain them together, but this involves separate pieces, which is generally more costly. It would be desirable, if possible, to combine the molding ease of plastic with the strength of steel in a cage structure having a simply shaped side rail, but which could be assembled without a metal deformation step.